1. Field of the Invention
The present disclosure relates to district public water supply pipe network system, and more particularly, to water supply pipe network system compatible for source side water for ground source heat pumping system and reclaimed water, which not only provides the ground source heat pumping system in the district with source side water as cooling/heating source, but provides the user in the district with reclaimed water, combining two networks together so that providing one network with dual functions.
2. Description of the Related Art
Energy resource, water resource and environment is perennial subjects of interest concern with the survival and development of human being. It is major challenges which the entire human race should face that how to conserve of energy and water and to protect the environment. For the purpose of energy conservation, water conservation and environmental conservation, various ground source heat pump technology and reclaimed water using technology are developed in the field in recent years. Ground source heat pump technology is an energy saving, environmentally friendly HVAC (Heat Ventilation and Air-Conditioning) technology, which utilizes energy stored in shallow geothermal energy resources in the earth surface such as rock soil mass, underground water, surface water, e.g. river, lake, sea etc., municipal sewage and waste water for cooling or heating. Because the shallow geothermal energy system in the earth surface has stable temperature all the year around, which makes the shallow geothermal energy system a benefiting cooling/heat source for water source heat pump units so that the water source heat pump unit could run in best operation condition, the COP (Coefficient of Performance) of ground-source heat pump is 30% higher than that of traditional air-conditioning. In addition, the ground-source heat pump does not discharge any pollutants to the environment, therefore, it is energy-saving and environmentally friendly. The shallow geothermal energy resource in the earth surface has extensive sources and is recyclable and inexhaustible, and it is known as a clean and renewable energy source which has attracted a wide range of attention and achieved rapid development. In accordance with heat sources and arrangements, the ground-source heat pump system may be classified as follows:
Ground coupled heat pump system: Vertical ground coupled heat pump system Horizontal ground coupled heat pump system
Ground water heat pump system: Direct ground water heat pump system Indirect ground water heat pump system
Surface water source heat pump system Open loop surface water source heat pump system Closed loop submersible pipe surface water source heat pump system Closed loop Intermediate heat exchange surface water source heat pump system
Sewage source heat pump system Direct sewage source heat pump system, i.e. untreated sewage source heat pump system Indirect sewage source heat pump system Reclaimed water source heat pump system
At present, ground-source heat pump is constructed as individual project, i.e. in accordance with the available resource, environment and execution conditions of individual buildings, specific type of ground source heat pump system is constructed, and operate individually. There are a lot of disadvantages for individual project development mode, which puts brake on development of the ground source heat pump technology.
At the same time, waste water treatment and reclaimed water utilization are effective way to deal with increasingly shortage of water resources. Reclaimed water is non-potable water which is obtained by deeply treating sewage and meets predetermined criterion and may be used within limits. According to statistics, 80% volume of urban water consumption is converted into sewage, 70% volume of which could be converted into reclaimed water after deeply treatment. This means that over 50% volume of urban water consumption may be converted into reclaimed water. Therefore, the reclaimed water resource is a water source with large volume, low cost and distribution convenience for urban area. In addition, it facilitates the development of urban sewage treatment and reduces the pollution of urban sewage. Sewage treatment and utilization of reclaimed water is economic and environmentally friendly. However, at present, the utilization of reclaimed water is unsatisfactory. The main reason is that the reclamation rate of the reclaimed water is low and the application area is not extensive. Therefore, on the one hand, the urban area has severe water shortages, which endangers people's health and daily life and affects the sustainable development of society and economy; on the other hand, if reclaimed water cannot be utilized, a lot of precious water resources would be wasting away.
Currently, the existing ground source heat pump technology and reclaimed water utilization technology mainly face the following defects:
The defects of existing ground source heat pump technology are as follows:
The construction mode of individual project restricts the large scale promotion of the ground source heat pump. For a construction project, whether to adopt a ground source heat pump system depends on its environment, resources conditions, hydrogeologic conditions, construction conditions, etc., which are great constraints for individual project making a lot of construction projects cannot adopt source heat pump system.
It is difficult to achieve energy balance. Energy balance is a principle which the development of ground source heat pump construction should follow. When a system discharges quantity of heat to the underground, the heat taken back from the underground should be fundamental equilibrium. Otherwise, if a district is kept in an energy imbalance state for a long time, its temperature field will be damaged, so that the rock and earth mass will be formed the “heat island” or “cold island”, or the quality of the surface water will be deteriorated and the environmental pollution will be formed, or the water temperature, water quality, water flow of the underground water will be damaged, or even the geological disasters will be made, etc. The existing individual ground source heat pump systems usually tend to adopt single kind of geothermal resource, which is difficult to achieve energy balance.
It is difficult to guarantee the quality of the cooling/heat source. The temperature of the cold/heat source is the key element to the energy-saving and efficient operation of the water source heat pump units. Generally, to maintain the water source heat pump units under the best working conditions, the temperature of the source side inflow water should be: about 25° C. for summer and 10 to 15° C. for winter. The temperature, beyond this range, whether too high or too low is not desirable. It will cause drop in efficiency, and rise in energy consumption in less severe cases; or even worse, it will cause the units break down and be out of service, or cause the unit shut down, the system break down, and the project fail. The development mode of individual project tends to adopt single form of geothermal resource, which usually has the nature of limitations and instability, and cannot fully guarantee the quality of the cooling/heat source, cannot guarantee the energy saving effect of ground source heat pump system, and cannot guarantee the sustained and stable operation of ground source heat pump system.
It is difficult to guarantee the quality of construction by the way of individual project. Ground source heat pump system is a complicated system, its development and construction must attach great importance to the science and technology, and implement strict construction norms and standards. However, individual project is often short of rigorous management, and its construction often does not conform standards, so that the construction quality is difficult to guarantee with lots of hidden troubles, which seriously influence the development of ground source heat pump technology.
Only limited development of shallow geothermal energy resources within certain district can be achieved. By the development mode of individual project, only limited development can be achieved within in a limited district by a few qualified building, and a lot of shallow geothermal energy resources within the district cannot be used.
The defects of the existing reclaimed water technology are as follows:
Cognitive mistake. It is believed that the reclaimed water is from sewage and not clean, and the quality of reclaimed water is poor. This makes people are lack of usage initiative.
The price. Currently, due to the technical and scale problem, the production and transportation cost of the reclaimed water is relatively high. The price difference between the reclaimed water and tap water is not obvious, therefore people are lack of profit-driven in the production and usage of reclaimed water.
Lack of water supply network, which causes the water cannot be supplied and becomes the bottleneck of the reclaimed water utilization.
The energy in the reclaimed water is cooling/heating source of high quality for water source heat pump units. It is common mistake that the reclaimed water can only be used as non-potable water with the energy in the water wasted.